Abstracting transformation for model driven architecture

ABSTRACT

An example embodiment of the present invention provides a process for abstracting an implementation-independent model to an implementation-specific model during transformation in a MDA system. In the example embodiment, the MDA system comprises a transformation engine whose components might include software tools such as AndroMDA and Muse. The transformation engine accepts as input an implementation-independent model written in a modeling language such as UML that provides graphical notation to describe inheritable classes and their attributes and relationships. The transformation engine also accepts a configuration file which allows the designation of a class in the model as a manageable resource. From these inputs, the transformation engine creates a manageable resource corresponding to the class, which resource includes any subclasses by inheritance from the designated class unless the subclass is specifically excluded in the configuration file. In one embodiment, the manageable resources created by the transformation engine are WSMD manageable resources.

TECHNICAL FIELD

The present disclosure relates to model driven architecture and modeldriven engineering.

BACKGROUND

Model Driven Architecture (MDA) is a framework for software developmentestablished by the Object Management. Group (OMG), which presentlymaintains the standard for the Unified Modeling Language (UML), anobject-oriented modeling language that includes graphical notation forclasses, their attributes, and their relationships to one another e.g.,inheritance, association, and composition). As to both MDA and UML, seegenerally Model-Driven Software Development, IBM Systems Journal, Volume45, Number 3 (2006).

The MDA framework generally involves three major steps. The first stepis to build a model of the software system at a high level ofabstraction so that the model is independent of any implementationtechnology. Typically this model is called a Platform Independent Model(PIM) and is written in a standard, well-defined modeling language suchas UML. The second step is to transform the PIM into one or morePlatform Specific Models (PSMs), each of which is tailored to a specificsystem in terms of the implementation constructs that are available inone specific implementation technology, e.g. a database model, anEnterprise JavaBean (EJB) model, etc. The third step is to transform aPSM to code—often code that supports the creation of a graphical userinterface (GUI), such as Java.

Because a PSM fits its technology very closely, the transformation inthe third step might be rather trivial in some instances, with thecomplex step being the second step in which a PIM is transformed to aPSM. Further an MDA transformation is typically executed by a softwaretool (e.g., a transformation engine), including both the transformationfrom a PIM to a PSM and the transformation from a PSM to code. Thus, onemight think of the modeling that creates the PIM as very high-levelprogramming.

Model Wizard is a software tool designed by Cisco that is based onEclipse and that provides utilities for manipulating models createdusing modeling tools such as IBM's Rational Software Modeler, which cancreate UML 2.0 models.

AndroMDA is a software tool for code generation, originated by MatthiasBohlen, which takes a UML model as input and generates source code asoutput. Via a series of template files, AndroMDA is capable of producingsource code in multiple programming and markup languages from a UMLmodel, though, by default, the programming language is Java. Morespecifically, the AndroMDA code generator is a generic code generationengine that hosts code modules (called cartridges) which do the actualcode generation. In turn, an AndroMDA cartridge is a collection ofsource code template files and Java helper classes (called Metafacades)packaged into a .JAR file. At the present time cartridges exist forWebService (e.g., the output can be WSDL files) and XMLSchema (e.g., theoutput can be XSD files), in addition to various Java platforms (e.g.,the output can be EJB files). Other MDA transformation engines also usecartridge modules.

Muse is a software tool maintained by the Apache Software Foundationthat implements the Web Services Distributed Management (WSDM):Management Using Web Services (MUWS) specification and createsWSDM-compliant interfaces from WSDL and XSD files. Those interfaces canthen be used to generate Java source code. The WSDM MUWS specificationis maintained by the Organization for the Advancement of StructuredInformation Standards (OASIS). The WSDM MUWS specification facilitatesthe distributed management (e.g., dynamic discovery and automatedredirection based on resource availability) of interoperablemachine-to-machine interaction over a network whose resources can beheterogeneous.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating, for didactic purposes, an example Webservice endpoint that provides access to a manageable resource,according to the WSDM MUWS specification.

FIG. 2 is a diagram illustrating, for didactic purposes, possibleresources which might be managed through Web services, according to theWSDM MUMS specification.

FIG. 3 is a UML diagram illustrating, for didactic purposes, a formalrepresentation of the WSDM MUWS specification.

FIG. 4 is a diagram illustrating an example system architecture on whicha transformation engine might execute in some embodiments of the presentinvention.

FIG. 5 is a diagram showing an example transformation engine, whichmight be used with some embodiments of the present invention.

FIGS. 6A-6D are diagrams showing an example XSD for a configurationfile, which XSD might be used with some embodiments of the presentinvention.

FIG. 7 is a class diagram showing an example UML model, which could beused with some embodiments of the present invention.

FIG. 8 is a diagram showing an example configuration file in XML format,which could be used with some embodiments of the present invention.

DESCRIPTION OF EXAMPLE EMBODIMENT(S)

In particular embodiments, the present invention provides methods,apparatuses, and systems directed to abstracting animplementation-independent model to an implementation-specific model(e.g., based on a particular platform or use case) during transformationin a MDA system. In a particular embodiment, the abstractingtransformation might be performed in conjunction with a transformationengine which includes components such as Model Wizard, AndroMDA, andMuse, taking a UML model as input and outputting WSDM-compliantinterfaces. The following example embodiments are described andillustrated in conjunction with apparatuses, methods, and systems whichare meant to be examples and illustrative, not limiting in scope.

A. WSDM MUWS Specification

By its own terms, the WSDM MUWS specification (MUWS 1.0 Part 1; Mar. 9,2005) defines how the manageability of an arbitrary resource can be madeaccessible via Web services. The WSDM MUWS specification is based on anumber of Web services specifications which mainly address messaging,description, discovery, accessing properties, and notifications. Thebasic concepts of management using Web services is illustrated in FIG.1, which shows a Web service endpoint that provides access to amanageable resource. An example of a manageable resource is a printerthat indicates when its toner is low, or, a magnetic storage disk thatreports its internal temperature, or a router that warns of a possibledenial of service attack. A manageability consumer discovers the Webservice endpoint and exchanges messages with the endpoint in order torequest information, subscribe to events, or, control the manageableresource associated with the endpoint. An example of a manageabilityconsumer is a management system, a business automation process or,simply, any Web service application.

In order to discover the Web service endpoint providing access to aparticular manageable resource, a manageability consumer first obtainsan Endpoint Reference (EPR) and then obtains any other requireddescriptions, including, but not limited to, a WSDL document, an XMLSchema, or a policy document. WSDM MUWS uses the same mechanisms, forobtaining EPRs and their associated descriptions as is used by regularWeb service implementations and their applications. A Web serviceendpoint providing access to some manageable resource is called amanageability endpoint. To exchange messages with a manageabilityendpoint, a manageability consumer makes use of available descriptionsfor the endpoint. The manageability consumer sends messages targeted tothe manageable resource using information contained in the EPR, forexample, an address and some reference properties.

FIG. 2 is a diagram illustrating, for didactic purposes, possibleresources which might be managed according to the WSDM MUWSspecification. As explained there, the WSDM architecture providesappropriate coverage from low-end manageability of small devices likemobile phones to high-end manageability of very capable components likeapplication servers, and business processes. This range of coverage isachieved by the low barrier to entry placed upon a WSDM implementationsince there are few normative requirements made by the specification andthe specifications on which it depends.

As shown in FIG. 2, a manageability consumer (which might be a machine)is connected to three manageable resources through Web serviceendpoints. The first manageable resource is a mobile phone whosemanageable capabilities include connectivity and identity. The secondmanageable resource is a printer whose manageable capabilities includeprinter management properties (e.g., paper or toner level), in additionto connectivity and identity. The third managed resource is a businessprocess whose manageable capabilities include business managementproperties (e.g., a metric for a task or activity), relationships, andavailability, in addition to connectivity and identity.

FIG. 3 is a UML diagram illustrating, for didactic purposes, a formalrepresentation of the WSDM MUWS specification. According to thisdiagram, a manageability consumer accesses a manageability endpoint(e.g., an EPR) in order to exercise the manageability capabilities of amanageable resource.

B. System Architecture for Transformation Engine

FIG. 4 illustrates, for didactic purposes, a hardware system 200, onwhich a transformation engine might execute. In some embodiments,hardware system 200 comprises a processor 202, a cache memory 204, andone or more software applications and drivers directed to the functionsdescribed herein. Additionally, hardware system 200 includes a highperformance input/output (I/O) bus 206 and a standard I/O bus 208. Ahost bridge 210 couples processor 202 to high performance I/O bus 206,whereas I/O bus bridge 212 couples the two buses 206 and 208 to eachother. A system memory 214 and multiple network/communication interfaces216 couple to bus 206. Hardware system 200 may further include videomemory shown) and a display device coupled to the video memory. Massstorage 218 and I/O ports 220 couple to bus 208. In some, but not all,embodiments, hardware system 200 may also include a keyboard andpointing device 222 and a display 224 coupled to bus 208. Collectively,these elements are intended to represent a broad category of computerhardware systems, including but not limited to general purpose computersystems based on the x86-compatible processors manufactured by IntelCorporation of Santa Clara, Calif., and the x86-compatible processorsmanufactured by Advanced Micro Devices (AMD), Inc., of Sunnyvale,Calif., as well as any other suitable processor.

The elements of hardware system 200 are described in greater detailbelow. In particular, network interfaces 216 provide communicationbetween hardware system 200 and any of a wide range of networks, such asan Ethernet (e.g., IEEE 802.3) network, etc. Mass storage 218 providespermanent storage for the data and programming instructions to performthe above described functions implemented in the RF coverage mapgenerator, whereas system memory 214 (e.g., DRAM) provides temporarystorage for the data and programming instructions when executed byprocessor 202. I/O ports 220 are one or more serial and/or parallelcommunication ports that provide communication between additionalperipheral devices, which may be coupled to hardware system 200.

Hardware system 200 may include a variety of system architectures; andvarious components of hardware system 200 may be rearranged. Forexample, cache 204 may be on-chip with processor 202. Alternatively,cache 204 and processor 202 may be packed together as a “processormodule,” with processor 202 being referred to as the “processor core.”Furthermore, certain embodiments of the present invention may notrequire nor include all of the above components. For example, theperipheral devices shown coupled to standard I/O bus 208 may couple tohigh performance I/O bus 206. In addition, in some embodiments only asingle bus may exist with the components of hardware system 200 beingcoupled to the single bus. Furthermore, hardware system 200 may includeadditional components, such as additional processors, storage devices,or memories.

The transformation engine described herein might be implemented as aseries of software routines run by hardware system 200, in particularembodiments. These software routines comprise a plurality or series ofinstructions to be executed by a processor in a hardware system, such asprocessor 202. Initially, the series of instructions are stored on astorage device, such as mass storage 218. However, the series ofinstructions can be stored on any suitable storage medium, such as adiskette, CD-ROM, ROM, EEPROM, etc. Furthermore, the series ofinstructions need not be stored locally, and could be received from aremote storage device, such as a server on a network, vianetwork/communication interfaces 216. The instructions are copied fromthe storage device, such as mass storage 218, into memory 214 and thenaccessed and executed by processor 202.

An operating system manages and controls the operation of hardwaresystem 200, including the input and output of data to and from softwareapplications (not shown). The operating system provides an interfacebetween the software applications being executed on the system and thehardware components of the system. The present invention may be usedwith any suitable operating system, such as the Windows®95/98/NT/2000/XP/Vista operating system, available from MicrosoftCorporation of Redmond, Wash., the Apple Macintosh Operating System,available from Apple, Inc., of Cupertino, Calif., UNIX operatingsystems, Linux, and the like.

C. Transformation Engine

FIG. 5 is a diagram showing an example transformation engine, whichmight be used with some embodiments of the present invention. As shownin the diagram, a full UML model is input into the Model Wizard, alongwith “blueprints” that specify a subset of the model that will make up atool or system of tools. In particular, the blueprints define theassociations, classes, interfaces, and properties required for the tool,system, or system of tools. The Model Wizard then exports a new model(e.g. in the EMX file format used by IBM's Rational Software Architect),which new model is a complete subset of the full model including anyadditional model object required to fulfill unspecified dependencies.The new model is then used as an input into AndroMDA to generate thedesired artifacts, be they Java interfaces, EJBs, Hibernate (anobject-relational mapping solution for Java) maps, WSDLs, and/or XSDs.Thereafter, additional processing of the artifacts might occur. Forexample, EJB artifacts might be input into an XDoclet plugin to generatewrappers. Or, WSDL and XSD artifacts might be input into Muse togenerate WSDM interfaces.

In particular embodiments of the present invention, one or moreinstances of classes in a full UML model (e.g. Managed Elements in theexample model below) might be exposed as a WSDM managed resource with aunique endpoint reference (e.g., based on the instanceID property in theexample model below), where the managed resource is defined using a WSDLfile that exposes standard WSDM operations (e.g., GetResourceProperty).Further, an attribute of a UML class might be defined as a standard WSDMcapability (e.g. a metric) of the corresponding managed resource using aresource property document in a separate XSD.

Also in particular embodiments, a configuration file for an AndroMDAcartridge might be used to define which classes will be treated asmanaged resources, where any subclasses would be treated similarly foreach defined class. Such a configuration file might also specify thatspecific attributes are to be treated as standard WSDM capabilities. Thelocation of the configuration file might be passed into the AndroMDAcartridge as the “WSDMConfigFile” property within the XSD-WSDLnamespace. In particular embodiments, the AndroMDA cartridge might be acustom AndroMDA cartridge that generates WSDM-compliant WSDLs and XSDs,using a template engine such as the Velocity software tool maintained bythe Apache Software Foundation.

D. Configuration File

FIGS. 6A-6D are diagrams showing an XSD for a configuration file, whichXSD might be used with some embodiments of the present invention. Asshown in the XSD, the root element for the XSD's hierarchy is“wsdmConfig”. At the next level of the hierarchy, there are three lists:(1) “managedResources”; (2) “properties”; and (3) “specNamespaces”.According to the XSD, managedResources consists of a list of one-to-manyelement-qualified names of classes from the model, other than the modelname. Specifically, if the element-qualified name of a class fallswithin “include” separators, the class corresponding to the name and anysubclasses, are to be treated as WSDM managed resources, unlessspecifically excluded. Likewise, if the element-qualified name of aclass from the model falls within “exclude” separators, the classcorresponding to the name and any subclasses are not to be treated asWSDM managed resources, unless specifically included. As shown in theXSD, a list of zero-to-many element-qualified names of classes from themodel might be excluded in this way.

Also as shown in the XSD in FIGS. 6A-6B, “properties” may include a listof zero-to-many element-qualified names for attributes or associationsfrom the model (other than the model name). Specifically, if theelement-qualified name of an attribute falls within “attribute”separators, the attribute corresponding to the name is to be treated asa WSDM capability of a WSDM managed resource. It will be appreciatedthat such an attribute is a WSRF property within the meaning of OASIS'sWeb Services Resource Framework (Version 1.2; Apr. 1, 2006). Also asshown by the XSD, such an attribute might have a “type”, which is anenumeration of a standard type of capability, and a “QName”, which isthe fully qualified name of the UML property.

In particular embodiments, the non-containing class of a composition iscomposed as an instance into the containing class, if the non-containingclass is to be treated as a WSDM capability or WSRF property. (Acomposition is a type of association in UML, as explained in detail byConrad Bock in UML 2 Composition Model, Journal of Object Technology,Vol. 3, No. 10, 2004). As shown by the XSD, this is accomplished bylisting the element-qualified name of a composition from the modelwithin “association” separators. Also as shown by the XSD, such acomposition might have a “name” attribute, which is the name to beapplied to the property, and a “QName” attribute, which is the fullyqualified name of the UML property.

Additionally, as shown by the XSD in FIG. 6D, “specNamespaces” includesa list of zero-to-many XML namespaces which might be used in the WSDMmanaged resources resulting from the configured transformation. An XMLnamespace is added to the list by including it within “namespace”separators. Such a namespace might have: (1) a “type” attribute whichindicates that it as an XSD or WSDL namespace definition; (2) a “prefix”attribute which indicates the namespace prefix; (3) a “uri” attributewhich indicates the namespace URI; and/or (4) a “location” attributewhich indicates the actual location of the namespace's XSD (e.g., a fileor URI).

To show further details of how to use a configuration file inconjunction with an abstracting transformation, an example is useful.FIG. 7 is a class diagram showing an example UML model, which could beused with some embodiments of the present invention. As shown in FIG. 7,the UML model includes a class called ManagedElement, which inherits(“is a”) from a base class called Top, which base class includesattributes called guiName and description (and the instanceID attributementioned earlier). The UML model also includes classes called Deviceand InternalDingbat which inherit from class ManagedElement. The classDevice has a composition relationship with class InternalDingbat, e.g.,a Device contains (“has a”) an InternalDingbat, as shown by theassociation DeviceHasDingbat. And likewise, the class Device has acomposition relationship with class DeviceSettings—e.g., a Devicecontains DeviceSettings, as shown by the association DeviceHasSetting.

FIG. 8 is a diagram showing an example configuration file in XML format,which could be used with some embodiments of the present invention. Itwill be appreciated that the configuration file in FIG. 8 conforms tothe XSD shown in FIG. 6, but implements a specific use case for the UMLmodel (e.g., it implements a more coarse-grain model based on thefine-grain UML model). Thus, the configuration file begins and ends withthe separator “wsdmConfig”. Next, there is a list of “managedResources”which “includes” the class ManageElement and excludes the class“InternalDingbat”. Then comes a list of “properties” which includes the(inherited) attribute, guiName, whose type is a caption, and theinherited attribute, description, whose type is a description. The listof “properties” also includes an association, DeviceHasSetting, whosename is “Settings”, and an association, DeviceHasDingbat. Theconfiguration file ends with a list of “specNamespaces”, which includesdefinitions of three generic XML namespaces (all of type xsd) whoserespective URIs and prefixes are (1) http://www.w3.org/2001/XML and xs;(2) http://schemas.xmlsoap.org/wsdl and wsdl; and (3)http://schemas.xmlsoap.org/wsdl/soap and soap.

In accordance with this configuration file, the class ManagedElement andall of its subclasses become a WSDM managed resource, except for thesubclass InternalDingbat and any of its subclasses. Also, in accordancewith this configuration file, the inherited attributes, guiName anddescription, become WSDM capabilities of the WSDM managed resourcecorresponding to class ManagedElement. Further, the DeviceSettingsinstance (at the non-containing end of the DeviceHasSetting composition)is composed into the Device class as a property, like the attribute,guiName, listed between the “attribute” separators. And theDeviceHasDingbat composition and the corresponding Internal Dingbatinstance are excluded from the WSDM managed resource (e.g., thegenerated WSDM-compliant XSDs and WSDLs).

Particular embodiments of the above-described transformation engine andconfiguration file might be comprised of instructions that are stored onstorage media. The instructions might be retrieved and executed by aprocessing system. The instructions are operational when executed by theprocessing system to direct the processing system to operate in accordwith the present invention. Some examples of instructions are software,program code, firmware, and microcode. Some examples of storage mediaare memory devices, tape, disks, integrated circuits, and servers. Theterm “processing system” refers to a single processing device or a groupof inter-operational processing devices. Some examples of processingdevices are integrated circuits and logic circuitry. Those skilled inthe art are familiar with instructions, storage media, and processingsystems.

Those skilled in the art will appreciate variations of theabove-described embodiments that fall within the scope of the invention.It will be appreciated that, in some embodiments, the modeling languagemight be other than UML or the transformation engine might includecomponents other than Model Wizard, AndroMDA, and Muse. Further, it willbe appreciated that a configuration file might be written in somemark-up language other than XML or in some language such as Perl orPython that is not a mark-up language. And it will be appreciated thatthe output of the transformation engine might be other thanWSDM-compliant interfaces. For example, the output might be Java or C#source code in some embodiments. Or the output might even be another UMLmodel, e.g., one abstracted for a particular use case. As a result, theinvention is not limited to the specific examples and illustrationsdiscussed above, but only by the following claims and their equivalents.

What is claimed is:
 1. A method, comprising: accepting, by one or morecomputing devices, as input at a transformation engine, a data filecontaining an implementation independent model written in a modelinglanguage, wherein the implementation independent model includes one ormore inheritable classes each of which includes zero or more attributesand zero or more relationships to another class; accepting, by one ormore computing devices, as input at the transformation engine, aconfiguration file designating as a manageable resource one or more ofthe inheritable classes included in the implementation independentmodel, wherein the manageable resource represents a device havingmanageable capabilities, the manageable capabilities comprisingconnectivity and identity, and wherein the configuration file identifiesone or more of the inheritable classes for exclusion; and outputting, byone or more computing devices, at the transformation engine, eachdesignated class as a manageable resource, wherein the manageableresource includes any subclasses by inheritance from the designatedclass unless excluded in the configuration file.
 2. The method of claim1, wherein the class relationships include association and composition.3. The method of claim 2, wherein the configuration file designates, asa manageable resource capability, a composition with a class designatedas a manageable resource and wherein the non-designated class in thecomposition is composed as an instance into the designated class when itis output by the transformation engine as a manageable resource.
 4. Themethod of claim 1, wherein the manageable resource is a WSDM manageableresource.
 5. The method of claim 1, wherein the configuration filedesignates, as a manageable resource capability, an attribute of a classdesignated as a manageable resource and the transformation engineoutputs the designated attribute as a manageable resource capability. 6.The method of claim 5, wherein the manageable resource capability is aWSDM capability.
 7. The method of claim 1, wherein the modeling languageis UML.
 8. The method of claim 1, wherein the transformation enginecomprises the AndroMDA transformation engine.
 9. The method of claim 1,wherein the transformation engine comprises the Muse software tool forcreating WSDM-compliant interfaces.
 10. Software stored in one or morecomputer-readable storage media for execution and when executed operableto: accept, as input at a transformation engine, a data file containingan implementation independent model written in a modeling language,wherein the implementation independent model includes one or moreinheritable classes each of which includes zero or more attributes andzero or more relationships to another class; accept, as input at thetransformation engine, a configuration file designating as a manageableresource one or more of the inheritable classes included in theimplementation independent model, wherein the manageable resourcerepresents a device having manageable capabilities, the manageablecapabilities comprising connectivity and identity, and wherein theconfiguration file identifies one or more of the inheritable classes forexclusion; and output, at the transformation engine, each designatedclass as a manageable resource, wherein the manageable resource includesany subclasses by inheritance from the designated class unless excludedin the configuration file.
 11. The software of claim 10, wherein theclass relationships include association and composition.
 12. Thesoftware of claim 11, wherein the configuration file designates, as amanageable resource capability, a composition with a class designated asa manageable resource and wherein the non-designated class in thecomposition is composed as an instance into the designated class when itis output by the transformation engine as a manageable resource.
 13. Thesoftware of claim 10, wherein the manageable resource is a WSDMmanageable resource.
 14. The software of claim 10, wherein theconfiguration file designates, as a manageable resource capability, anattribute of a class designated as a manageable resource and thetransformation engine outputs the designated attribute as a manageableresource capability.
 15. The software of claim 14, wherein themanageable resource capability is a WSDM capability.
 16. The software ofclaim 10, wherein the modeling language is UML.
 17. The software ofclaim 10, wherein the transformation engine comprises the AndroMDAtransformation engine.
 18. The software of claim 10, wherein thetransformation engine comprises the Muse software tool for creatingWSDM-compliant interfaces.
 19. An apparatus, comprising: means foraccepting, as input at a transformation engine, a data file containingan implementation independent model written in a modeling language,wherein the implementation independent model includes one or moreinheritable classes each of which includes zero or more attributes andzero or more relationships to another class; means for accepting, asinput at the transformation engine, a configuration file designating asa manageable resource one or more of the inheritable classes included inthe implementation independent model, wherein the manageable resourcerepresents a device having manageable capabilities, the manageablecapabilities comprising connectivity and identity, and wherein theconfiguration file identifies one or more of the inheritable classes forexclusion; and means for outputting, at the transformation engine, eachdesignated class as a manageable resource, wherein the manageableresource includes any subclasses by inheritance from the designatedclass unless excluded in the configuration file.
 20. The apparatus ofclaim 19, wherein the manageable resource is a WSDM manageable resource.